1. Technical Field
Various embodiments relate generally to a semiconductor memory device and a method of manufacturing the same and, more particularly, to a three-dimensional non-volatile memory device and a method of manufacturing the same.
2. Related Art
A non-volatile memory device retains data stored therein even when not powered. Two-dimensional memory devices in which memory cells are fabricated on a single layer over a silicon substrate have reached physical limits in increasing their degree of integration. Accordingly, three-dimensional (3D) non-volatile memory devices in which memory cells are stacked in a vertical direction over a silicon substrate have been proposed.
A 3D non-volatile memory device includes memory cells and select transistors that are stacked over a substrate. These memory cells include a memory layer to store data. The memory layer may include a tunnel insulating layer, a charge storing layer, and a charge blocking layer.
When a 3D non-volatile memory device is manufactured, memory cells and select transistors are formed concurrently. The select transistors may also include a memory layer that acts as a gate insulating layer. However, when the memory layer is used as the gate insulating layer, a leakage current of the select transistors may increase.